The present invention relates to the refrigeration industry and, more particularly, to the field of commercial refrigeration air handlers and related methods
In a commercial refrigeration apparatus, an evaporator is generally positioned within an interior region of a refrigeration container. For example, in a refrigeration apparatus positioned within a grocery store, e.g., a refrigeration display case having a glass door or an open refrigeration display case having no door, the evaporator is generally positioned along a bottom inner periphery of the refrigeration container. Applicant has recognized that this configuration tends to create numerous maintenance problems such as evaporator accessibility and clogging of drain lines, especially during transitions from defrost cycles. The evaporator positioned within the refrigeration container typically includes intake and output ducts. The configuration of the intake and output ducts, however, also cause maintenance problems in that they become easily clogged with various items that fall to the bottom of the refrigeration container, e.g., price tags and bits of food, during these cycles. Clogged intake and output ducts significantly decrease the efficiency of the refrigeration system.
In the case of walk-in refrigeration units, the evaporator is generally suspended from a top inner periphery of the refrigeration container. Applicant has recognized that condensation from the evaporator generally tends to accumulate especially during frost cycles, presenting various problems including potential health hazards. Another problem that exists with a walk-in refrigeration apparatus having an evaporator suspended from a top inner periphery of the refrigeration container is electrical maintenance. Electrical wiring to and from such evaporators are positioned within the refrigeration container closely adjacent a great deal of condensation which can occur during defrost cycles which often occur three to six times per day, for example, in commercial refrigeration units. The condensation can sometimes cause shorts and other electrical malfunctions, raising another potential hazard. Still another problem that exists with the walk-in refrigeration units is cleanliness and sanitation, i.e., condensation changes from defrost cycles from the suspended evaporators tends to drip onto food and other consumable items stored in the walk-in refrigeration container, causing a serious health risk.
Applicant has also recognized that another problem that commonly exists in a refrigeration apparatus having an evaporator positioned within the refrigeration container is that drain lines tend to freeze when positioned within the refrigeration container. When the condensed liquid in the drain lines freezes, it tends to expand and the drain lines can therefore sometimes burst.
Positioning components of a refrigeration apparatus exterior a refrigeration container is known as can be seen in U.S. Pat. No. 6,070,424 to Bauman et al. titled Modular Refrigeration Unit. Applicant has recognized, however, that the configuration of a condenser and evaporator positioned closely adjacent one another is highly inefficient and is not well suited for commercial applications, such as refrigeration systems for grocery stores. A more energy efficient and low maintenance refrigeration system is still needed.
With the foregoing in mind, the present invention advantageously provides a more efficient refrigeration system and apparatus, a more efficient evaporator apparatus, a refrigeration apparatus conversion kit for converting existing refrigeration apparatuses into more energy and cost efficient refrigeration apparatuses, and associated methods that greatly reduces maintenance needs, enhance energy efficiency, especially during defrost cycles, and reduce various hazards associated with existing refrigeration systems and apparatuses. For example, because an evaporator is removed from the interior of a refrigeration container and placed at a location exterior to and preferably on top of the refrigeration container, significantly less energy is required to defrost or heat the evaporator for the refrigeration container. Because the evaporator is positioned outside of the refrigeration container and preferably in an insulated housing on top of the refrigeration container, less area of the evaporator to heat is required for defrost cycles which can occur about 3-6 times per day, the evaporator then uses much less energy to defrost. Accordingly, for grocery stores or other structures which contain numerous evaporators for refrigeration containers, the energy saving during defrost cycles can be tremendous.
The refrigeration system and apparatus of the present invention also advantageously identifies the source of the problems associated with sanitation and cleanliness within a refrigeration container, and solves this problem by connecting an evaporator to exterior portions of a refrigeration container. The present invention also advantageously identifies and solves the problem of cleanliness and sanitation with existing refrigeration containers by removing collected condensate from the refrigeration system before it can be introduced to an interior portion of the refrigeration container.
The present invention also identifies and solves problems associated with energy efficiency of a refrigeration system by positioning an evaporator to overlie exterior portions of the refrigeration container so that warm air residing towards an interior upper portion of the refrigeration container is readily removed from the refrigeration container and so that cool air introduced towards the interior upper portion of the refrigeration container settles towards a lower interior portion of the refrigeration container without the need of excess application of a fan motor. The present invention further advantageously identifies the source of problems associated with increased maintenance costs of refrigeration systems and provides unique solutions of providing ready access to the evaporator positioned exterior the refrigeration container such as providing an enhanced air curtain and substantially eliminating blowing streams of air. The present invention further advantageously identifies the source of the problems associated with increased maintenance costs due to increased maintenance calls required when an evaporator is positioned within a refrigeration container.
More particularly, the present invention preferably includes a refrigeration system having a plurality of refrigeration containers positioned in a predetermined area. The refrigeration system also preferably includes a plurality of thermally insulated housings positioned within the predetermined area to overlie the plurality of refrigeration containers so that one thermally insulated housing overlies one refrigeration container. Each of the thermally insulated housings preferably includes an intake and an output. The refrigeration system further preferably includes a plurality of evaporators positioned within the predetermined area and within the plurality of insulated housings between the intake and the output so that one of the plurality of evaporators is positioned within one of the plurality of thermally insulated housings to move warm air from within the refrigeration container, through an intake opening formed in the refrigeration container, into the intake of the insulated housing, over the evaporator through an output opening formed in the refrigeration container, and into the refrigeration container as cooled air. The cooled air flowing downwardly from the output opening preferably defines a cool air curtain positioned adjacent a front wall of the refrigeration container. The cool air curtain advantageously allows air to be distributed more evenly than a straight directed blow or blast of cool air and advantageously reduces damage to walls of a refrigeration container and food positioned in the refrigeration container.
The refrigeration system of the present invention still further preferably includes a plurality of condensers positioned exterior the predetermined area and connected to the plurality of evaporators positioned within the predetermined area. The refrigeration system of the present invention also preferably includes a plurality of drain pans positioned within the predetermined area so that a respective one of each of the plurality of drain pans underlies a respective one of the plurality of evaporators positioned within the thermally insulated housings to collect condensate from each of the plurality of evaporators. The refrigeration system further preferably includes a common drain line positioned within the predetermined area so that the common drain line is positioned adjacent the plurality of drain pans and so that the condensate collected in each of the drain pans is readily removed to a position exterior the predetermined area. The common drain line, for example, can be positioned to extend adjacent each of the refrigeration containers, preferably above ground, to reduce installation and plumbing costs, and extends to a common, e.g., by a single if desired, drain in the ground or floor of a store. For example, 15-20 refrigeration containers can advantageously be connected to the common drain line, e.g., by a xe2x80x9cTxe2x80x9d connection above ground and fluid or drainage passing through the pipe can be deposited into a single drain which then extends outside of the predetermined area, e.g., outside of the building.
The refrigeration apparatus of the present invention preferably includes a refrigeration container and at least one thermally insulated housing positioned to overlie the refrigeration container. The at least one thermally insulated housing preferably includes an intake and an output positioned so that the intake of the at least one thermally insulated housing overlies an intake opening of the refrigeration container and the output of the at least one thermally insulated housing overlies an output opening of the refrigeration container. The refrigeration apparatus also preferably includes at least one evaporator positioned within the at least one thermally insulated housing between the intake and the output to overlie the bottom of the insulated housing. The refrigeration apparatus further preferably includes a drain pan positioned to underlie the at least one evaporator within the at least one insulated housing to collect condensate from the at least one evaporator.
The evaporator apparatus of the present invention is preferably adapted to be positioned to overlie a refrigeration container to remove air having a first predetermined temperature from the refrigeration container and replace it with air having a second predetermined temperature that is substantially lower than the first predetermined temperature. The evaporator apparatus preferably includes a thermally insulated housing including a bottom, a top positioned spaced-apart from and overlying the bottom, and a plurality of sidewalls positioned to extend between the bottom and the top. The plurality of sidewalls are preferably defined by a first sidewall, a second sidewall positioned substantially opposite the first sidewall, a front sidewall, and a rear sidewall positioned substantially opposite the front sidewall. The insulated housing further preferably includes an intake positioned adjacent the first sidewall and an output positioned adjacent the second sidewall. The evaporator apparatus of the present invention further preferably includes an evaporator positioned within the insulated housing. The evaporator preferably includes a plurality of fans positioned at a predetermined angle adjacent the intake of the thermally insulated housing to extend substantially the length of the first sidewall and a cooling coil positioned adjacent the plurality of fans between the intake and the output to extend substantially the same length as the plurality of fans. The fans are preferably adapted to readily direct the air having the first predetermined temperature into the thermally insulated housing through the intake and over the cooling coil to thereby then define the air having the first predetermined temperature as the air having the second predetermined temperature. The plurality of fans further preferably direct the air having the second predetermined temperature through the output of the thermally insulated housing.
The refrigeration apparatus conversion kit of the present invention is preferably adapted to convert a refrigeration apparatus having an evaporator positioned within a refrigeration container into a refrigeration apparatus having an evaporator positioned exterior the refrigeration container. The refrigeration apparatus conversion kit preferably includes a container, an evaporator positioned within the container, and a template positioned within the container to outline dimensions of a pair of openings to be formed in a top outer surface of the refrigeration container. The refrigeration apparatus conversion kit also preferably includes a pair of duct inserts positioned within the container to be inserted in the pair of openings formed in the top outer surface of the refrigeration container.
The present invention also advantageously includes a method of cooling air positioned in a grocery store refrigeration container. The method preferably includes extracting air having a first predetermined temperature from an upper portion of the grocery store refrigeration container, cooling the extracted air to a second predetermined temperature that is substantially lower than the first predetermined temperature, and introducing the air having the second predetermined temperature into the grocery store refrigeration container. The present invention also advantageously includes a method of converting a refrigeration container having an evaporator positioned within the refrigeration container to a refrigeration container having an evaporator apparatus positioned exterior the refrigeration container. The method preferably includes removing the evaporator positioned within the refrigeration container, forming a pair of openings in an outer surface of the refrigeration container, and installing the evaporator apparatus exterior the refrigeration container to overlie the pair of openings formed in the refrigeration container.
The present invention further advantageously includes a method of draining condensate from an evaporator apparatus connected to and overlying a refrigeration container positioned within a grocery store building so that the condensate does not contact interior portions of the refrigeration container. The method preferably includes positioning a drain pan to underlie an evaporator positioned within an evaporator apparatus to collect the condensate from the evaporator, and extending a drain line from the drain pan to a position spaced-apart from the refrigeration container and exterior to the grocery store building so that the condensate is readily removed from the evaporator apparatus without contacting the interior portions of the refrigeration container.
The present invention advantageously prevents the freezing of drain lines in a refrigeration system by positioning drain lines exterior the refrigeration container. The present invention also advantageously enhances maintenance cost savings of refrigeration systems by recognizing and solving the source of problems associated with clogging of evaporators, such as during defrost cycles, positioned within the refrigeration container and, the clogging of associated drain lines positioned within the refrigeration container. The present invention further advantageously enhances the efficiency of a refrigeration system and greatly reduces the cost of operating and maintaining the refrigeration system.